This invention relates generally to a valve means for application within a flow line, and more particularly pertains to a reinforced pivotal butterfly valve prepared for industrial applications and which incoporates bushings and packing means to sustain the useful life and application of the valve during installation and continuous usage.
The current invention is intended as an improvement upon the standard technology pertaining to disc valves that are currently in existence and for application for industrial usage. For example, disc valves of this type are frequently utilized within materials flow lines, whether it be the type of material which may be of fluid consistency, or even of granular material and which are flowed to or from a storage bin either for accumulation therein, or to a location for shipment for storage or usage. For example, disc valves of this type are frequently applied into the flow lines connecting with a tank trailer, and of the type which can and are used for the transportation or storage of fluids, such as liquids, or even other granular materials, that are frequently shipped by transit. It is likewise applicable that the disc valve of this type may also be used generally in tubular flow lines, whether they be used in association with the loading and unloading of barges, ships, or other means of transportation or storage.
The type of disc valve normally employed for this purpose, and which functions as a shutoff of flow through a conveyor in which these type of materials may be conveyed, are generally shown in various prior art patents, such as the U.S. Pat. No. 2,740,423, to Stillwagon, and therein identified as a valve for usage for these subject purposes. Another U.S. Pat. No. 2,994,342, Stillwagon, discloses further improvements upon this style of valve, and more specifically the sealing means used in conjunction therewith. In addition, Stillwagon possesses yet another U.S. Pat. No. 3,100,500, upon a disc valve with a removable seat and a unitary stem incorporating its disc, and a seat and stem wear-sleeve therefor. Finally, there is a U.S. Pat. No. 3,241,806, to Snell, Jr., disclosing a disc type valve having a plastic layer on its resilient seating surface. The current invention, as distinct from these earlier models of disc valves for use for industrial purposes, incorporates the technology of utilizing a disc type valve within a flow tube, having a stem mounted for pivotal movement, incorporating a resilient seat against which the disc valve can seal when arranged into closure, but the subject matter of this invention incorporates counterbores within the apertures formed for seating of the valve stem, and in which polymer, and preferably acetal stem bushings are arranged to provide for the convenient and low frictional mounting of the disc valve and its stem within the tubular housing, and which is likewise resistant to corrosion, and fatigue.
It is, therefore, the principal object of this invention to provide discrete bushings arranged for mounting within predisposed counterbores formed within apertures arranged diametrically of the flow passage through a materials passing tubular housing, and into which a disc valve and its stem may be pivotally mounted for precise turning therein between its open and materials passing condition to its closed and sealed position against its resilient seat.
Another object of this invention is to provide the arrangement of counterbores diametrically disposed within a tubular housing, one of which opens into the flow passage through the said housing, while the other counterbore opens exteriorlly of the housing, in order to facilitate the assembly of the stem mounted disc valve into its operative position within the housing during assembly and installation.
Another object of this invention is to provide bushings used in conjunction with a disc valve within an industrial butterfly valve assmbly, and which bushings reduce the frictional engagement of the valve stem during its manipulation, are resistant to any immediate wear, and prevent any corrosion occuring between the stem and the housing in which it pivotally mounts.
Another object of this invention is to provide a stem packing that locates proximate the stem bushing within one of the apertures provided through the tubular housing, so as to seal off that aperture against leakage, and to assure a positive seal for a pressure or vacuum service of the butterfly valve during its industrial applications.
Another object of this invention is to provide a corresponding counterbore provided for the aperture for mounting of the opposite extending stem of a disc valve, and which counterbore and aperture do not extend through the tubular housing so as to provide an automatic seal against leakage and to further insure that positive seal for the pressure or vacuum service of the valve when applied in industrial applications.
These and other objects will become more apparent to those skilled in the art upon reviewing the summary of this invention, and upon undertaking a study of the description of its preferred embodiment in view of the drawings.